举例

　　1) A good case in point is ...

　　2) As an illustration, we may take ...

　　3) Such examples might be given easily.

　　4) ...is often cited as an example.

证明

　　1) No one can deny the fact that ...

　　2) The idea is hardly supported by facts.

　　3) Unfortunately, none of the available data shows ...

　　4) Recent studies indicate that ...

　　5) There is sufficient evidence to show that ...

　　6) According to statistics proved by ..., it can be seen that ...

开篇

　　1) Many nations have been faced with the problem of ...

　　2) Recently the problem has been brought into focus.

　　3) Recently the phenomenon has become a heated topic.

　　4) Recently the issue has aroused great concern among ...

　　5) Nowadays there is a growing concern over ...

　　6) Never in our history has the idea that ... been so popular.

　7) Faced with ..., quite a few people argue that ...

　　8) According to a recent survey, ...

　　9) With the rapid development of ..., ...